Blends of elastomers with modified phenolic resins



Patented Oct. 27, 1953 UNITED STATES OFFICE BLENDS OF ELASTOMERS- WITH MODIFIED" PHENGLIC RESINST David W.. Young, Roselle, and-Raymond G. Newberg, Cranfordg, J., assignors to Standard Oil; Development Company a.. corporation 01' Delaware.

N Drawing; Application August 19, 1948, Serial No. 45,208:

11 claims... (01. zed-171.2)

This invention relates to plasticized phenolic resins of improved resiliency and flexibility, and more particularly to blends of a certain type of modified phenolic resins with copolymers of the diene-nitrile type.

A limited number of blends of phenol-aldehyde resins with difierent' kinds of-rubber have been known in the art previously. However, none of the blends previously known had the unique combination of properties which distinguish the blends of thepresent invention, the latter having excellent flexibility,- unusual extensibility, good bags and the like. Even'more unexpectedly, the

novel blends WBIefOlllldj to' be quitesuperiorin their heat flow characteristics which make them an excellent materialformolding. large articles such as pieces of furniture, chemical. reactor vesselsand the like, where it 'has' been known by contrast that phenolic resins of themselves or their previously known blends were not too'well suited? for the 'moldingof large objects because they tended" to set prematurely before filling the mol'd'evenly and, therefore, lead" to a large. proportion' of rejects. or resulted in' prodi'i'ctsjwithv rough surfaces requiring; expensive polishing op,- erations. The addition of the rubbery'copolymers described hereinafter apparently over comes this disadvantageby retarding the'xprefmature cure ofthe phenolicresin' without adversely affecting its final cured, properties or usually even improving thelatter.

Theitwoprincipal materials used. in the present' invention are:

A. A modified phenolidresin obtained bycondensing an. aldehyde, preferably formaldehyde, with a meta-or: parai'hydrocarbon' substituted;

phenol having about 1-0 to, about.2-1;carb on atoms inthe aliphatic hydrocarbon substituent.

may be saturated or may have one or two double bonds. Suitable phenols include meta decyl' phenol or its homologues up'to or the corresponding para substituted analogue;

or preferably the corresponding unsaturated analogues such as cardanol may be obtained by alkyla atingphenol-f with polypropylene having 12 to- 21 carbon atoms per molecule. However, a particularly useful unsaturated a-lkylated phenolic materialis; cardanolto: which the formula has' been; assigned andwhich is obtained'by. distillation of cashew nutshell oil (as described in Industrial and Engineering; Ghemistry, volume-'32, page 1309;,October 194.0) andstill another excellent; material isranacardicacid (ether extract of cashew nut; shells), which isbelieved to p SSSSEQIj-diO1QfiI1iC substitution group; or the phenolic liquid, obtainable by polymerizing cashew nut shell liquid at moderate, temperatures with the helpgofani alkyl suliate canlikewise be used fcr theyaldehydecondensation;

The phenohaldehydei condensation reaction is carried; ou-,t;=irr the usual, known manner at: temperatures; ran ing-dram- 6.0 0;. to 150 C., the heating; usually beingijaccomplished, by a steam jacket maintainedpat. about; C. toi 0.; and; using: the; usual: known basic: or acid catalys a, i m hy roxide or'sulfuricacid; the condensation roducts being, dehydrated" in the latter; stages: of the-reaction at temperatures of about;1 10f- C. to JLSQ to form a fusible resin;

purposes of the present invention the modified phenolic or condensation polymer may contain an activator, e. g., 2 to 10 percent of hexamethylene tetramine (which yields formaldehyde on further heating) if fast curing blends of high tensile strength are required. All of these resins are fluid when heated to about 80 0., some being liquid even at room temperature. These condensation polymers of formaldehyde with a substituted phenol having 10 to 21 carbon atoms in the aliphatic substituent will hereafter be referred for brevitys sake as long chain alkyl phenolic resins, it being understood that the aliphatic substituent may be a saturated alkyl group or an unsaturated hydrocarbon radical.

B. The other principal material used in the blends of the invention is an elastomer prepared by copolymerizing in aqueous emulsion 20 to 35 or 40 parts of acrylonitrile or methyacrylonitrile, with 80 to 65 or 60 parts of a conjugated diolefin of 4 to 6 carbon atoms such as butadiene-1,3,

of course that many modifications or variations of these examples are possible without departing from the scope of the invention.

Example I In this and all following illustrative examples, unless otherwise specified, the novel blends were prepared by first breaking down the diene-nitrile polymer on differential rolls at 40 C. (four passes) and then milling in the liquid or solid phenolic resins on a rubber mill at 55 C. over a period of 15 minutes. Milling temperatures between 45 C. and 65 C. are generally desirable in dealing this type of thermosettin resins, since these tend to cure or scorch at temperatures higher than. about 80 C. The blended stocks were then cured for 15 minutes at 163 C. in a standard ASTM four-cavity mold (13-15-41) yielding slabs 6" x 6" x 0.075", all stocks being cured between cellophane to eliminate possible adhesion to the molds. Test specimens were out from the resulting rubbery or leathery stocks and when tested gave the following results:

TABLE I Blend l 2 3 1 4 l 5 6 7 8 9 10 Nitrile-bntadione elastornen parts (35% combined acrylonitrile) 100 ill 90 c0 80 7O 70 60 60 5O 50 Ordinary modified pllenol resin, 5 l0 ..l n, 30 4O 50 Long-chain alkyl phenolic resin, parts 3 l0 5 l l Tensile strength, lbs/sq. in 500 700 400 1,150 600 l, 650 l, 200 2, 150 l, 950 3, 300 2, 800 Elongation, percent 510 470 475 400 4-15 300 350 200 260 100 180 Tear strength, lbs/inch (ASlllI 13-024 110 50 i3 110 310 200 620 580 720 680 Shore hardness (A duronietcr) i ii- D-GTG- MT) 55 50 9O 8O 95 stillness, lbs/sq. in. l0 (AS'lM D-7 l7: i 0 0 5 0 22 12 42 Brittleness, C. (ASTM D6%44) l0 45. 6 34.4 35. 7 29 29 1 Perbun n 35 NS; uncured. 2 Durez I7 (eondensat 3 Cardoiite 1 (condens isoprene or dimethyl butadiene. As is well known, in preparing these elastomers the preferred monomers such as butadiene and acrylonitrile are emulsified in water or other aqueous medium with the help of an emulsifier such as sodium oleate or other alkali soap of a higher fatty acid, or with the help of synthetic dispersing agents of the sulfonate type, and the emulsion is thereafter polymerized at temperatures between about 10 and 65 C. in the presence of an oxygenyielding catalyst such as hydrogen peroxide, benzoyl peroxide, potassium persulfate or other alkali metal persulfates or perborates or mixtures thereof. Usually, it is also desirable to add to the polymerizable mixture a minor amount of a polymerization modifier, e. g., a mercaptan of 6 to 18 carbon atoms such as lauryl mercaptan, or a commercial mixture of mercaptans known as Lorol mercaptan which consists predominantly of lauryl mercaptan with minor amounts of other mercaptans in the C6 to C18 range. The polymerization is normally continued until about 70 to percent of the monomers are converted to form the desired copolymers, which usually have a Mooney viscosity of 60 to as determined by the use of a large rotor (2 minutes at 100 C.). For the sake of brevity, these known copolymers will hereinafter be referred to simply as diene-nitrile elastomers. However, for certain purposes it is also possible to use oily copolymers of the diolefin-nitriie type, instead of the rubbery copolymers just described.

The following specific examples will serve to illustrate the unexpected advantages of the present invention, although it will be understood ion product of [ormaldehydeand tertiary butyl phenol).

ion product 01'' formaldehyde and cardanol; contains about 5% of added hexaincthylenototramine) From the data summarized in Table I, it can be seen that the novel blends of nitrile-diene elastoiners with the long-chain allryl phenolic resins have satisfactory properties, in many respects comparable to blends of the same elas tomers with ordinary unmodified or even the low-alkyl modified phenolic resins. Thus, the cured blends containing up to about 50 percent of resin by weight resemble vulcanized rubber having tensile strength between about 460 and 3500 lbs/sq. inch. Furthermore, it can be observed from the data of Table I that the novel blends containing less than about 30 percent of the long-chain allry1 phenolic resin are very substantially weaker than the analogous control blends of the unmodified or low-allzyl modified phenolics and have very nearly the same elongation as the latter. However, quite surprisingly, at the critical limit of about 30 percent resin content and higher, the novel blends containing the long-chain alkyl phenolic resin become very much more extensible than the analogous control blends, while at the same time attaining a tensile strength only slightly inferior to that of the latter.

fThis unexpected effect of the long-chain alkyl phenolics when used in proportions above the critical limit is brought out clearly by a comparison of blends lying on either side of the critical limit, e. g., of the 20%blends 3 and i, with the 30%blends 5 and 5. Such a comparison shows that blend 4, having an elongation which is greater by only 15 points in 409 than control blend 3, has a rather poor tensile strength well below 1000 lbs/sq. inch, and only 2,65%185; 61 about one-half that of blend 3;v in contrast, The results obtained upon curing-the various blend: 61 having an elongationwhich is. greater compounds for minutes: at; 1639 are sum-' by 50 points in 30Dthan control= blend 5; has a marizedin Table II- AB I.

Blend. Run. 1'. ii. 112: 1s 14 r5. l6 5 17 1&1 T19 2o. a 2i i 23."

series" 0 Nitrile-butadiene elastomer parts Ordinary modified phenolic resin parts.. Long-chain alkyl phenolic resin, parts- Long-chain alkyl phenolciresin' parts Tensile strength, lbs/sq. inch I. Elongation, percent Ultimate elasticityfactor. lQ?,in. lbs.[cu.in 37.5 78 71 41 8] 1 75.t 60..v 4U=. 84. 'Z2i 12. T

Footnotes l, 2, and 3 sameasl, 2, and 3 of Table I.

4 Gardolite 899 (no hexa'rnethylene tetramin e). h The ultimate elasticity'fac'tor is the product of ultimate tensile strength expressed in lbs/sq. in. multiplied by iltimate elongation expressed in inch linch, and is ameasureoi olasticenergy per unit volume.

good tensile strength well above 1000 lbs/sq. inch and only. about. 28.. percent; lower. thanthe indicate the entirely unexpected." superiority in tensile strength of the control blend. even terms of elongation or extensibility of" the long; more striking difference is broughtout by com-. paring the 50%,..-.blends. a and' 1-0; the latter least 30 percent in rubber-resin blends, as comhaving almost twice the elongation of the ared to the extensibility of blends; containing former, while at; the same. time having the exordinary unallgylated or even; short-chain, alkyfcellent tensile strength of 2800. lbs/sq. inch, ated phenolic resins; Irrhiglr resin concentrawhich is only 15% lower than the control blendq9. tions, the extensibility of" the novel blends This difference in properties due to the use especially outstanding, cured blends of 235 of the long-chain alkylj phenolic resins in elasto containing asmuch as a two-to one ratio. of long;- mer blends, represents a very significant im chain alkyl phenolic resin to, rubber beingshown provement especially where the blends are to to possess an elongation of-3 60% as comparedto be used for high; steam pressure expansion gasthe very slight elongation of 20% exhibited by kets, or as gaskets in pipelines subjectto, thermal the corresponding blend ofjRun 21 containing or other expansion; or in articles flexible at low theordinary phenolic resin; temperatures. Another important, advantage of Moreover; with thelong-chain allgylatedf phenthe'novel' blends ofelastomer and resin is inolics, it is possible to use blends much richer herent in the fact that they" can be cured; by in resin. content and still obtain compounds of" heatand in the absenceof sulfur, the: phenolic excellent elongation and tensile strength'. This resin by itself apparently causing the elastomer is shown by a comparison; or-Runs 15* and" 19; to cure by a mechanism not yet satisfactorily 40 wherein thedatter contain n 50 chlong-chain explained. When the novel blends are cured in alkylated resin; has substantially identical tensile the absence of sulfur, they yield products which properties asthe former" which contains only not only possess excellent tensile. strength: com- 33 /3'% of phenolic resin. It can; be-seen that the parable torthat of similar. blends-employingunnovelblends can be formulated to; yield com-- modified or low-al-kyl modified phenolic resins, pounds possessed ofan unusual combination of but which. at the same time. possess remarkable properties, that is, a resin content; of 3'5 to-70;%, extensibility even when. the. resin is contained. an elongation of at least 250 to-800-%-- and anin the blendlconcentra tions of to 70 per-. ultimate elasticity factor ofat lea-st 4000 inch; cent, whereas. similar blends. of the unmodified pounds/in the simultaneous presence of theorlow-alkyl modified phenolic resins become 50 st pulated h gh elongation and relatively higlr verynearly rigid at. resin concentrations;v at orelasticity factor being indicative'of' goodtensile above 50; percent. This. combination of high strength. and goodextensibility or low! stiffness. strength of at least about; 25.00 tov 3590: lbs/sq. The po s ili y: f t us using higher concentra inch, substantial ultimate elongation of; at least tions of the relatively, cheaplongschainz alkylatert bout 5. o 3, 0% @fid. 9l?% ;a. e-0fS 111 phenolic i to eplece ome-of ghefainly eXgfur is of obvious importance where.-strong flexpensive diene-nitrile elastomer, without any ible products are required as gaskets or the like major Sacrifice in he elas-tic..properties of the in conveying or containing. fine liquid chemicals ed compound, is, of course, of great economic which must be preserved free from sulfur. i n fi ance-.-

no r nt ng. s lt; disclos d by Eable- 6O Emmple H II is that while; the. highly exten cm Where sulfuris. not; objectionablein the final blends. of nitrile rubber with theslong product, conventional rubber compounding. in-

edients. may also be advantageously. used: in strength than th corresponding blends. of ordithe novel elastomer-resin blends with; interesting nary phenolics, this diiference canbe decreased substantially by selecting a long ehain alkyl' phenolic resin containing an activator such as, hexamethylene tetram-inewhicli liberates formaldehyde on heating andthus causes a more results. In this example, blends of. varying. 612131. miner-resin:proportions.wereprepared-in;accord: anc e; wtih the following: basic-formula:

Iar sbr Wei h Phenolic resin. plus dienemitrfl elastomer 7 advanced cure of theresin on heating as' shown (variable proportions) 1 00 bylihe ies hereby the eventual Zinc-oxide 5 t n ile strengthcan be incr ased-ver substay. Stearic acid 1 i lly, though at thesame time some reduction Sulfur 2 of ultimate elongation will res lt k yclohexyl-flebenzothiazole.sulfenamide 1 It is also interesting to compare the results The results shown in Table II again; clearly chain alkyl phenolic resin in concentrations; of at;

phenolic resins of series; 3, areweaken tensile- 7 of Table II, series 2, with the results of Table I, the comparison showing that a significant increase in both tensile strength and ultimate elongation can be obtained by adding vulcanizing agents for the elastomer component to the blend prior to curing.

Furthermore, the difierent results illustrate how a resin blend possessing the best balance of desired properties can be formulated for any given purpose. Thus, a desired shift in properties can be achieved by changing on or more of the following principal variables: ratio of elastomer to resin; presence or absence of usual curing agents for the rubbery constituent; presence or absence of fillers and/or plasticizers; and presence or absence of a curing aid for the longchain alkyl phenolic resin such as hexamethylene tetramine or a free aldehyde. The rubber curing agents may b any of the known materials used for this purpose, e. g., l to weight percent of sulfur, 0.2 to 3 weight percent of organic Vulcanization accelerators such as benzothiazyl disulfide, tetrainethyl thiuram disulfide, N-cyclohexyl 2-benzothiazole sulfenamide, diphenyl guanidine, zinc diethyl dithiocarbamate, etc

The usual auxiliary compounding and ouring aids, fillers, pigments, anti-oxidants and dyes may also be present. Compounds typical of the aforementioned classes are higher fatty acids, such as stearic acid, which may be present in amounts ranging from 0.5 to 5 percent based on the total blend; 0.5 to 60 percent or preferably one to 5 percent of basic metal oxides in the form of zinc oxide, lead oxide, magnesia, basic lead oxide, basic lead carbonate, lead silicate, and hydrated lime. Carbon black, mica, talc, barytes, clay, asbestos, lithopone, cotton and wood fibres, wood flour, etc, may likewise be used in conjunction with the blends of the present invention. Furthermore, many plasticizers, such as dibutyl phthalate, dioctyl phthalate, trimethyl phosphate, various hydrocarbon polymers, such as solid copolymers of styrene with approximately equal amounts of iosobutylene prepared by Friedel-Crafts polymerization at temperatures below about 70 F., are also useful for modifying the blends of the present invention; the particular advantages of the styrene-isobutylene polymers being described and claimed in copending application Serial No. 48,752, filed September 10, 1948. The blended compounds are usually cured in molds at temperatures between 90 and 180 C. for periods ranging from 2 minutes to 60 minutes, or preferably for to 20 minutes at 150 to 165 C.

Example III lite 904) 50 Zinc oxide 5 Sulfur 1.5 Stearic acid 1.5 Benzothiazyl disulfide 1.5

The two stocks were identical in composition except that the diene-nitrile copolymer of stock A had a combined acrylonitrile content of 26% (Perbunan 26 NS whereas the corresponding copolymer of stock B had a combined nitrile content of 35% (Perbunan 35 NS 90). When tested the two stocks were characterized by the following properties:

TABLE III A (26% nitrile) B (35% nitrile) Oven Oven Stock aged aged Original Original 12 at at 212 F. 212 F.

Shore hardness 84 84 81 84 Tensile strength, lbs./

sq: in l 1, 200 l, 140 l, 600 l, 530 Elongation, percent 350 210 430 250 Modulus at elongation, lbs/sq. inch 620 620 Specific gravity 1.079 1.093 Orescenttearresistance,

lbs/inch 270 290 Brittle temperature,

C. (ASTM D-746- 441) 34. 5 -23. 5 Stiffness in flex at 24 0.,1 s./sq. inch (ASTM D747-4Sl) 3, 240 3, 760

Immersed at room temperature, hours 24 168 24 168 Volume increase, percent in:

ASTM reference fuel No. 1 2.2 5.7 0.9 2.7 ASTM reference fuel No. 2 42.7 62.1 35.5 43.8 ASTM Oil No. 3.-. 0.7 1.3 0.4 0.6 Water 0.6 1.8 0.8 1.9

The above data illustrate that an increase in the nitrile content of the diene-nitrile elastomer contributes significantly to an improvement in tensile properties of the blend, the tensile strength as well as the elongation of the 35%- nitrile stock being greater than the corresponding values for the 25%-nitrile stock. Furthermore, the high nitrile stock also shows substantially better resistance to tear and to hydrocarbon solvents. On the other hand, the low nitrile stock is superior in regard to low temperature properties, water resistance and resistance to polar solvents generally, and is also characterized by a lower flex stiffness.

Example IV Blends of up to about 50% resin content are rubbery or leathery in character. However, analogous blends of a predominantly rigid and structurally strong character suitable for molding radio cabinets, filing cabinets, furniture generally, tool handles, automobile fenders, and the like can also be formulated, the presence of the rubbery diene-nitrile polymer having a highly beneficial effect on the impact strength and brittle temperature of the blends.

Blends illustrative of compositions suitable for molding were compounded in the usual manner and their properties were determined on molded slabs preformed at 104 C. and 1200 lbs/sq. in. ram pressure and cured 20 minutes at 163 C. The results obtained are summarized below.

TABLE Compound 1 2 3 4 5 Long-chain Alkylated Phenolic resin, parts by weight 100 90 90 80 80 74% butadiene-26% acrylonitrile copolymer, parts by weight--. 65% butadiene-% acrylonitrile copolymer, parts by weight. l0 20 Woodi'lour, parts by weight 50 50 50 .50 50 Hexamethylene tetramine,

parts by weight 4 4. 4 4 4 Izod impact strength, ft. lbs./

inch of notch 0. 490 (l. 542 0.580 0. 629 0.697 Tonsil strength, lbs/sq. inch 4, 760 4, 280 4-, 740 3, 910 4, 600 Flexural strength, lbs/sq. inch. 8, 920 7, 670 8, 710 7, 120 7, 830 Compression strength, lbs./

sq. inch 33, 100 21, 600 25, 640 17,100 18,200 Percent compression 12.8 12.4 12.3 11.7 11.1 Rockwell hardness (M scale) 121 86 110 72 86 1 Cardolite 904. 2 Perbunan 26 NS 90. 3 Perbunan 35 NS 90.

The foregoing results illustrate the very substantial improvement of impact strength obtained by adding a minor amount of rubbery nitrile-cliche polymer to the phenolic resin.

In addition to the uses previously described, the novel blends can also be dissolved in methyl ethyl ketone or other solvents capable of dissolving the phenolic resin as well as the elastomer, to reduce the blend to a consistency of putty or even to brushing consistency, and the resulting mixture or solution can be applied as an adherent layer to metal or other surfaces to protect them from corrosion and other advers effects. Still other modifications of and uses for the compounds described hereinbefore will be thought of by persons skilled in the art without departing from the inventive concept claimed, and it is to be understood that the foregoing examples have been set forth hereinabove only as illustrations, but not as limitations of the invention defined in the appended claims.

We claim:

1. A composition of matter comprising 30 to 60 parts of a resin prepared by condensing formaldehyde with an aliphatically substituted phenol having as its only substituent a C10 to C21 hydrocarbon side chain selected from the group consisting of alkyl radicals, monoolefinic radicals and diolefinic radicals; in combination with 70 to parts of a solid rubbery copolymer of 20 to 35 percent of acrylonitrile and 80 to 65 percent of butadiene-l, 3, the resin having been incorporated in the copolymer while the resin was in a fusible state.

2. An extensible composition of matter comprising 30 to parts of a fusible resin prepared by condensing formaldehyde with cashew nut shell oil and '70 to 55 parts of a solid rubbery copolymer of 25 to 35 percent of acrylonitrile and '75 to 65 percent of butadiene-1,3.

3. A cured, sulfur-free extensible composition of matter comprising to '70 parts of a resin prepared by condensing formaldehyde with a phenol having as its substituent, a mono-ethylenically unsaturated hydrocarbon side chain of from 10 to 21 carbon atoms and 50 to 30 parts of a solid rubbery copolymer of 20 to 26 percent of acrylonitrile and 80 to '74 percent of butadiene-1,3, the resin having been mixed with the copolymer while the resin was in a fusible state; said composition being characterized by an ultimate elongation of at least 150 to 250 percent and a tensile 10 strength of 2500 to 3500 pounds per square inch.

4. A cured composition of matter comprising 30 to '70 parts of a resin prepared by condensing formaldehyde with distilled cashew nut shell oil; '70 to 55 parts of a solid rubbery copolymer of 20 to 35 percent of acrylonitrile and to 65 percent of butadiene; and 1 to 5 parts of sulfur.

5. A cured composition of matter comprising 35 to 7.0 parts by weight of a resin prepared by condensing formaldehyde with distilled cashew nut shell =oil 65 to 30 parts by weight of. a solid rubbery copolymer of about 26 percent of acrylonitrile and about '74 percent of butadiene; and 1 to 5 parts by weight of sulfur and a vulcanization accelerator; said composition being characterized by an ultimate elongation of 250 to 800 percent and an ultimate elasticity factor of at least 4000 inch pounds per cubic inch.

6. A cured composition of matter comprising parts of a solid rubbery copolymer of 25 to 35 percent of acrylonitrile and 75 to 65 percent of butadiene-1,3; 50 parts of a resin prepared by condensing one mol proportion of formaldehyde and 0.75 to 1.5 mol proportions of cardanol; 5 parts of zinc oxide; 1.5 parts of sulfur, 1.5 parts of stearic acid and 1.5 parts of benzothiazyl disulfide; said composition being characterized by a tensile strength between 1200 to 1600 lbs/sq. inch, an elongation between 350 and 430 percent, and brittle temperature between -20 C. and 35 C.

7. A method comprising mixing at a temperature between 45 C. and 65 C., 30 to 60 parts of a reactive fusible resin prepared by condensing formaldehyde with a phenol having a monoethylenically unsaturated side chain of 10 to 21 carbon atoms in the meta position, and 70 to 4.0 parts of a solid rubbery copolymer of 20 to 35 percent of acrylonitrile and 80 to 65 percent of butadiene, and curing the resulting mixture in the absence of any sulfur curing agent for the rubbery copolymer as well as any aldehyde curing aid for the resin at a temperature between and C.

8. A method according to claim '7 wherein the reactive resin is essentially a condensation product of formaldehyde with cardanol and contains between 5 and 10 percent of its weight'of hexamethylene tetramine.

9. A method comprising mill mixing at a temperature between 50 C. and 60 C., 30 to 45 parts of a fusible resin prepared by condensing formaldehyde with cashew nut shell oil, '70 to 55 parts of a solid rubbery copolymer of 25 to 35 percent of acrylonitrile and '75 to 65 percent of butadiene, 1 to 5 parts of sulfur, 0.2 to 3 parts of an organic vulcanization accelerator, 1 to 5 parts of zinc oxide and 0.5 to 5 parts of stearic acid; and curing the resulting mixture at a temperature between 150 and 180 C. for a period of 2 to 60 minutes.

10. A composition of matter which comprises about 90 parts of a resin prepared by condensing formaldehyde with cashew nut shell oil, about 10 parts of a rubbery copolymer of about 65% butadiene and 35% of acrylonitrile and about 50 parts of woodfiour.

11'. A composition of matter comprising 30 to 90 parts of a fusible aliphatically substituted phenol-formaldehyde condensation resin wherein each aromatic ring of the condensation product has a sole hydrocarbon substituent of from 10 to 21 carbon atoms selected from the group consisting of alkylated radicals, mono-olefinic radicals and diolefinic radicals and '70 to 10 parts of a copolymer of 2,0 to 35% of acrylonitrile and 80 to 65% of a conjugated butadiene hydrocarbon 01 Number Name Date from L to 6 carbon atoms per molecule. 2,452,374 Harvey Oct. 26, 1948 2,459,739 Groten et a1 Jan. 18, 1949 DAVID YOUNG 2,532,374 Shepard Dec. 5, 1950 RAYMOND G. NEWBERG.

OTHER REFERENCES Newberg et a1., Rubber Age, February 1948, pp. 533-539.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date Morgan Paint Manufacture, March 1945, pages 2,310,077 Harvey Feb. 2, 1943 10 73-75 2325331 sarbach Aug 3 1943 Cardohte, pub. 1947 by Irvmgton Varmsh and 2,441,360 Whetstone May 13, 1943 Insulator Co., Irvington, N, J pages 1, 2 and 4. 

1. A COMPOSITION OF MATTER COMPRISING 30 TO 60 PARTS OF A RESIN PREPARED BY CONDENSING FORMALDEHYDE WITH AN ALIPHATICALLY SUBSTITUTED PHENOL HAVING AS ITS ONLY SUBSTITUTED A C10 TO C21 HYDROCARBON SIDE CHAIN SELECTED FROM THE GROUP CONSISTING OF ALKYL RADICALS, MONOOLEFINIC RADICALS AND DIOLEFINIC RADICALS; IN COMBINATION WITH 70 TO 40 PARTS OF A SOLID RUBBERY COPOLYMER OF 20 TO 35 PERCENT OF ACRYLONITRILE AND 80 TO 65 PERCENT OF BUTADIENE-1 3, THE RESIN HAVING BEEN INCOPORATED IN THE COPOLYMER WHILE THE RESIN WAS IN A FUSIBLE STATE. 